Various optical networks have been previously proposed for transmitting information including but not limited to audio, video and data from one location to another. Originally, the fiber optic industry used single wavelength transmission links. Multiplexing based on wavelength has been utilized more and more in optical networks to greatly increase transmission capacity over single wavelength transmission links. Specifically, wavelength division multiplexing (WDM) was developed to transmit two optical signals each having a distinct wavelength on a single waveguide. In response to the ever increasing demand, coarse wavelength division multiplexing (CWDM) was developed to further increase the transmission capacity of optical networks. CWDM allows generally up to eight different channels to be stacked with channel spacing of 20 nm. To accommodate even greater transmission capacity demands, dense wavelength division multiplexing (DWDM) has been developed to send a large number of closely spaced optical signals over a single fiber. DWDM systems have channels spaced as close as 0.2 nm.
Several companies have developed component or network products with reconfigurable add/drop multiplexers (ROADM) to permit remote reconfiguration of the wavelength division multiplexers to eliminate or reduce the requirement of a site visit to the node to alter or replace a fixed add/drop multiplexer to achieve the desired modification of the network. Examples of these reconfigurable add/drop multiplexer products are available from companies such as JDSU, Capella Photonics, LightConnect, etc.
As the complexity of optical networks increases with the ever increasing demand for greater network capacity, the task of developing and designing networks is more and more daunting. For example, there are many choices in the technology used to implement OADM nodes. The more sophisticated and advanced the technology, the greater the capability and functionality of the nodes, but generally at the expense of increased costs and reduced reliability. Substantial network-wide benefit can be realized by introducing sophisticated but costly technology only on as-needed basis in the network. Currently, network design and OADM technology selection is predominantly done by estimating only local node requirements, without much regard for the interactions that may span large portions of the network. This process generally produces network designs that are severely suboptimal either in terms of robustness, or in terms of cost.
Accordingly, there exists a need for a method in which variables of an optical network can be readily determined to optimize the network. The variables include but are not limited to the placement of components (e.g., filters, regenerators, wavelength converters, etc.) in the optical network.